SCH 4U
Name: _____________________
Unit: Structure and Properties of Matter
Date: _____________________
Unit Review
The unit test will be held on Friday 6 November. This is a Day 2. You may begin at 8:15 a.m. if you wish. When the final
class bell rings, test writing time is over. If you have an IEP and wish to write in Resource please let your teacher know
asap. If you are in this position and are expecting extra time, it is also your responsibility to inform the classroom teacher
of any other class you may miss and to catch up on missed work. Should you be absent on test day, your parents will be
contacted to confirm the reason for absence and you are expected to be ready to write the test the day you return to
school. An answer key to this unit review will be posted on the class website by Monday 2 November.
Part A: Historical Contributions to the Atomic Model
1. Describe a major problem with the Rutherford model of the atom that Bohr addressed with his model.
2. Describe at least one major problem with the Bohr model of the atom.
3. Describe the significance of the following to the Bohr model of the atom: line spectra, absorption spectra, photons, quanta
of energy.
Part B: Quantum Mechanical Model of the Atom (QMT – quantum mechanical theory)
1.
Outline the differences between orbits and orbitals.
2.
Draw an orbital diagram (box and arrow) diagram for:
a)
51
V
23
b)
3.
Write the electronic configuration for:
a)
75
As
33
b)
Note that the electron configuration for Cu is not as expected.
Why is this? (See page 196.)
4.
5.
6.
Write the electron configurations for each of the following.
a) (shorthand) Sr
b) (shorthand) bromine
c) Fe+2
32
S
16
59
Ni
28
c)
91
Zr
40
c)
65
Cu
29
d) S2-
Identify another ion or an atom that is isoelectronic to S2-.
What are the quantum numbers n, l and ml for each of the orbitals of:
a) the 5p sublevel
b) the 6d sublevel
7.
Show or state the location of each of the following sets of quantum numbers:
1
a) n = 2,
l = 1,
ml = 0
ms = + 2
1
b) n = 6,
l = 3,
ml = - 1
ms = - 2
1
c) n = 7,
l = 1,
ml = + 1,
ms = - 2
8.
Define and be able to use the following terms: aufbau principle, Hund’s Rule, Heisenberg Uncertainty Principle, Pauli
exclusion principle.
9.
Why do Cu and Cr have unexpected electron configurations?
10. Textbook questions: page 255 #34; page 258 #13
Part C: Trends in the Periodic Table for Atomic Radius and Electronegativity
1.
2.
Describe the trends seen in the periodic table for both atomic radius and electronegativity and be able to explain them.
Textbook problems page 255 #32, 33; page 259 #19, 20
Part D: Properties of Solids (pg. 268-273)
This was a section you were assigned to do on your own.
1.
2.
Name the 4 types of solids. Describe the major differences between them.
Consider the following properties of three substances.
Substance
I
II
III
3.
Boiling
Point (K)
1770
2220
2630
Electrical Conductivity
of solid of liquid
poor
good
poor
good
good
good
Identify each substance as a molecular solid, network solid, metal or ionic compound. Briefly justify your choice.
Textbook problems: page 254 #18, 19, 26, 27; page 255 #46; page 258 #12.
Part E: Valence Bond Theory and Orbital Hybridization
1. Consider a central atom with hybrid sp3d orbitals.
a) What type of orbitals and how many of each type combine to make sp3d hybridized orbitals?
b) How many sp3d orbitals exist on the atom?
c) What VSEPR formula and shape would be characteristic of a molecule with a central atom exhibiting sp 3d
hybridization if the central atom had
i) no lone pairs?
ii) 1 lone pair?
iii) 2 lone pairs?
iv) 3 lone pairs?
d) Underneath each of your answers to part c) above, draw a 3-D diagram to represent each of the molecular
shapes.
e) Why do all of the central atoms in all of the molecules in part c) have the same orbital hybridization?
2. There are five major VSEPR shapes from which the rest are derived when one or more lone pairs are added to
the central atom. These five major shapes are: linear, trigonal planar, tetrahedral, trigonal bipyramidal and
octahedral. Each of these five major VSEPR shapes has its own characteristic type of hybridization on the
central atom and characteristic bond angles. Match each of the five major shapes below with the name of the
shape of the hybrid orbitals on the central atom.
The Five Major VSEPR Shapes
Orbital Hybridization
A.
B.
____ sp3d
____ sp
____ sp3d2
C.
____ sp2
D.
____ sp3
E.
3. In a general sense, what effect do lone pairs on a central atom have on the bond angles of trigonal planar,
tetrahedral, trigonal bipyramidal and octahedral VSEPR shapes? Explain why the effect occurs.
4. Label each of the bonds in the following molecule as a sigma bond, σ,or as a pi bond,π. Label each carbon atom
with the hybridization its orbitals exhibit.
CH2
5. Describe two differences between sigma and
pi bonds.
H3C
6.
7.
C
C
CH
Define the terms “hybridization of orbitals” and “hybrid orbitals”. When and why does hybridization occur?
Textbook problems: page 254 #13,
Part F: Lewis Structures, VSEPR Theory, Molecular Polarity
1. You have a list of rules for determining a Lewis structure. Make yourself a table with the following headings and then fill it
in for each of the following substances. An example has been included under the table headings so you can see what to do.
Substance
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6
Step 7
Skeleton
Total no.
Electrons in
Complete
Place any
If central atom
Lots of finishing
structure
valence
pairs in bonds
octets of
remaining
still needs an
touches are
electrons
atoms
electrons on
octet, form
required for the
attached to
the central
multiple bonds
final structure.
central atom
atom
LOOK THEM UP!!!
CO2
C is
central
atom
2O
1C
O C O
12 e14 e116 e1-
O
C
O
O
C
O
O
C
O
O
C
O
O
C
Aren’t any
extras…
Substances to put into your table:
a) SbCl5 (Watch for expanded valence on Sb. Elements in period 3 and lower, like Sb, can often make more bonds than are
predicted by the octet rule. This is explained in your Lewis structure notes.)
b) SF6 (Watch for expanded valence on S.)
c) NH41+ (This substance exhibits co-ordinate covalent bonding. This occurs when a covalent bond forms where one atom
contributes both electrons to the shared pair. A co-ordinate covalent bond looks and acts no different than a
regular single bond, it is just formed slightly differently. Indicate the co-ordinate covalent bond in this
polyatomic ion on your Lewis structure.)
d) BF3
e) NH3
f) HCN
g) XeF4 (Under certain conditions, noble gases can be made to form molecules.)
h) O3 (This is ozone. It is a resonance structure. Be sure to show this in the final column of your table.)
i) ClF3
j) HCl
k) BrF5
2. For each of the molecules above,
i) determine the VSEPR formula ii) determine the VSEPR shape
iii) Draw a 3-D diagram to show the VSEPR theory
shape and write in the (approximate) bond angles.
3. Textbook problems: page 255 #22, 28, 39, 35; page 257 #59; page 259 #21, 22
Part G: Intermolecular Forces
1.
2.
3.
4.
5.
6a)
Explain the difference between intermolecular forces and intramolecular forces.
List the 3 different types of intermolecular forces and distinguish between them.
How are intermolecular forces linked to the properties of molecules?
In Part F, question #1 you drew a 3-D diagram for SF6. Add bond dipoles and partial charges to a copy of the 3 – D
diagram. State whether this molecule would be polar or non-polar and explain your reasoning.
In Part F, question #1 you drew a 3-D diagram for BrF5. Add bond dipoles and partial charges to a copy of the 3 – D
diagram. State whether this molecule would be polar or non-polar and explain your reasoning.
Write in the bond dipoles and partial charges as necessary on the bonds in the molecules drawn below. State whether
each molecule would be polar or non-polar. Identify all of the intermolecular forces that would exist between neighboring
molecules of the same type in each case.
Molar mass = 46 g/mol
Molar mass = 46 g/mol
O
H
C
H
Intermolecular forces between neighboring molecules of
this type are:
O
H
C
H
N
H
Molar Mass = 45 g/mol
Intermolecular forces
between neighboring
molecules of this type:
O
Intermolecular forces between neighboring molecules of
this type are :
6b) Rank the three compounds from part a) from
highest to lowest boiling boiling point. Explain
your answer.
7. Do page 255 #36, 40, 42, 43, 44; page 255 #17, 23
O